Legal Risk Mitigation in Hydrogen Pipeline Transport through Corrective Action Order Analysis

Federal enforcement is central to ensuring United States (US) pipeline safety and reliability, yet little research has examined how enforcement patterns evolve or reflect regulatory priorities. This study analyzes 76 corrective action orders (CAOs) issued by the Pipeline and Hazardous Materials Safety Administration (PHMSA) from 2011 to 2025 to identify the dominant drivers, patterns, and implications of federal corrective enforcement. Descriptive and statistical analyses, including the Kruskal-Wallis H-test and two-way analysis of variance (ANOVA), demonstrate that enforcement actions are concentrated in operational and technical domains, emphasizing immediate hazard containment and diagnostic verification. Cause of failure and administrative region were significantly influencing enforcement complexity, with rupture incidents leading to more extensive regulatory actions. Analysis also revealed significant interaction between region and material and material and cause, suggesting that enforcement intensity increases when materials coincide with high-risk failures in specific regions. Based on these findings, the study develops a hydrogen CAO-readiness matrix that maps observed enforcement triggers to hydrogen-specific contractual safety provisions, providing a proactive framework for emerging hydrogen infrastructure regulation. The results underscore PHMSA’s role as a learning-oriented, risk-responsive regulator and demonstrate how empirical enforcement data can inform forward-looking safety governance across energy transition systems.